---
title: QLPreviewProvider
framework: quicklook
role: symbol
role_heading: Class
path: quicklook/qlpreviewprovider
---

# QLPreviewProvider

## Declaration

```swift
class QLPreviewProvider
```

## Overview

Overview Data-based preview extensions should subclass QLPreviewProvider in their principal object. The subclass should conform to QLPreviewingController.

## Relationships

### Inherits From

- [NSObject](objectivec/nsobject-swift.class.md)

### Conforms To

- [CVarArg](swift/cvararg.md)
- [CustomDebugStringConvertible](swift/customdebugstringconvertible.md)
- [CustomStringConvertible](swift/customstringconvertible.md)
- [Equatable](swift/equatable.md)
- [Hashable](swift/hashable.md)
- [NSExtensionRequestHandling](foundation/nsextensionrequesthandling.md)
- [NSObjectProtocol](objectivec/nsobjectprotocol.md)

## See Also

### QuickLookUI symbols

- [QLFilePreviewRequest](quicklook/qlfilepreviewrequest.md)
- [QLPreviewReply](quicklook/qlpreviewreply.md)
- [QLPreviewReplyAttachment](quicklook/qlpreviewreplyattachment.md)
- [QLPreviewItem](quicklook/qlpreviewitem.md)
- [QLPreviewingController](quicklook/qlpreviewingcontroller.md)